Among the many adjustments Stevens has made is handling
the highs and lows.

“This is what I think is borderline hilarious,” Stevens said. “You can go through a tough [stretch] — and we have and you can be just completely at the bottom, and every day you’re hurting and every day you feel like you don’t know when the next win is coming.

“And then you go on a run. And, all of the sudden, you feel like you’re unbeatable. It’s funny, because it happens in such a short amount of time. In college, there’s four games in two weeks. Here, there may be eight or nine, depending on the weeks.

“That’s the biggest difference.”

But Stevens believes he has grown, along with the Celtics, who now have a 14-28 record.

“We have had some really good moments,” Stevens said. “I think we’ve also let some slip away. That bothers me, probably more so than I’ve let on.”

When asked about the state of the team at the halfway point, president of basketball operations Danny Ainge said, “I’m happy with where we are.

“I’m not really happy with our record, but I really don’t spend much time [on that],” Ainge continued. “I’m looking at each individual, trying to figure out who we want with us in the future. I couldn’t be happier working with Brad and what he’s doing. We’ve got some guys that are really developing that I see that are getting better.”

The second half of the season figures to be different, if only because Rajon Rondo has rejoined the Celtics after sitting out nearly a year with a knee injury.

“I think it’s slowly getting there, slowly getting a little more settled,” Ainge said. “We still have a lot to evaluate in the second half of the year. I think that with Rondo coming back, obviously there’s going to be an adjustment for him. We need to be really patient for him. I think it’s unfair to really judge him on the first handful of games at least — maybe the month.

“But we’re just looking for progress. And guys like Kelly [Olynyk] and Phil [Pressey] and Jared [Sullinger] and Avery [Bradley] have really, really developed. Vitor [Faverani] has had some ups and downs, as Kelly has, just because we have a lot of bigs and sometimes they don’t get as many minutes. Kris Humphries has had a terrific year. I think Brandon [Bass] has had a terrific year.

“There’s a lot of good things.”

Rondo on the clock

Two days after playing his first game in nearly a year, Rondo said that he feels fine overall and that his right knee — the one he had surgically repaired after tearing the anterior cruciate ligament on Jan. 25, 2013 — feels OK, too.

“I’m alive. I’m walking. I’m well. I feel fine,” the point guard said before morning shootaround. “It’s been a while since I played, but I’m fine.”

Rondo played on a five-minute-per-quarter rule during his season debut Friday against the Lakers and again against the Magic, and it figures that he’ll be on that system for a while.

“I think that will be the case until I’m told otherwise,” Stevens said. “Our medical staff is really good. I trust them to do the right thing by our players.”

Stevens added that the most Rondo would play in one of the opening three quarters was five minutes. “And then we’ll go from there,” he said.

He added, “And let’s say you played him 12 in the first three quarters and then eight in the fourth, I think you’re testing conditioning a little bit. I do think the five-minute stints are probably best.”

In terms of Rondo’s minutes restriction, Stevens said there is no timeline.

“I’m guessing it will be at least for the first week, maybe more, in that minutes restriction,” Stevens said. “Again, how we divvy those up or how we space those out — I don’t know what the right answer is to that. I do think it’s important that he’s playing at the end [of games], like he did the other night, because that’s part of getting back in the groove of things.”

When asked about those minute restrictions, Rondo said, “It’s not frustrating. I want to be patient. I knew going into it that it would be 20 minutes. It’s the first time in my career where I’ve had limitations, but it’s part of it. It won’t last forever. It’s temporary.”

He added, “I’m not the first guy to do this, and I won’t be the last. I’ll adapt and I’ll adjust, and I’ll make the best of the 20 minutes.”

Rondo watched film of himself after Friday’s game and said he felt OK about how he had performed, for the most part.

“I haven’t had a preseason or training camp or even any other games to play,” Rondo said. “I try not to get too down on myself.”

Brotherly love

Kevin Garnett and Paul Pierce might be with the Brooklyn Nets, but both of the former Celtics said they’re glad to see Rondo back in action, especially in time for the two teams to face off Jan. 26 at TD Garden. “That’s my little brother,” Garnett said, according to the New York Post. “I love Rondo. He knows that, and I would do anything for him. All in all, I’m just happy that he’s back, and I’m just happy he’s able to be healthy and continue to be able to do one of the things he does best.” Said Pierce, “I mean, I thought he would be back a lot sooner than this week. Obviously, he’s just taking his time, making sure he’s 100 percent, which he should do, and I expect him to be out there anyway.” . . . Jeff Green slipped and twisted his right knee during the second quarter when he tried to close on a defender. He left the game, but later returned and said that he felt fine . . . Jerryd Bayless left the game in the third quarter with a sprain of his left big toe. It’s unclear if he’ll play Tuesday against Miami.